/*
 * Copyright (C) 2022 panpf <panpfpanpf@outlook.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.panpf.sketch.request.internal

import com.github.panpf.sketch.request.ImageRequest
import com.github.panpf.sketch.request.ProgressListener
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Deferred
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.async

class ProgressListenerDelegate<REQUEST : ImageRequest>(
    private val coroutineScope: CoroutineScope,
    private val progressListener: ProgressListener<REQUEST>
) {

    private var lastDeferred: Deferred<*>? = null

    fun onUpdateProgress(request: REQUEST, totalLength: Long, completedLength: Long) {
        val lastDeferred = this.lastDeferred
        if (lastDeferred?.isActive == true) {
            lastDeferred.cancel()
        }
        this.lastDeferred = coroutineScope.async(Dispatchers.Main) {
            progressListener.onUpdateProgress(request, totalLength, completedLength)
        }
    }
}